The primary purpose of this research proposal is to evaluate the influence of menstrual cycle changes on smoking cessation and relapse on women subjects following their participation in smoking intervention program. Ninety-six women will participate in a behavioral self-management program designed to address issues of weight control and stress reduction, factors known to be of specific importance to women smokers. There are three major aims of the proposed study. First, the association between the date of relapse and menstrual cycle phase will be examined. Menstrual cycle data and relapse assessments will be collected weekly for one year of follow-up in order to determine the point where slips and relapses occur in the cycle. Second, the association between severity of withdrawal and the phase of the cycle women are in when they quit smoking will be explored as well as the association between the overall severity of withdrawal and menstrual distress that women experience. Third, the study will evaluate the influence of weight changes on women who are successful long-term quitters as compared to those who may quit for a short period of time or those who are non-quitters. The knowledge gained from these data and additional demographic and biological factors that may contribute to women's success in cessation and relapse prevention will benefit the development of future smoking intervention programs for women.